Effectiveness of a microabrasion technique using 16% HCL with manual application on fluorotic teeth: A series of studies

Table 1 Patient distribution by age and gender

	Number of patients	Age	Std. deviation
Female	33	13 yr, 11 mo	1.33
Male	24	13 yr, 11 mo	0.96
Total	57	13 yr, 11 mo	1.16

Table 2 Descriptive statistics of procedure time in minutes (n = 84)

	Minimum	Maximum	mean ± SD
Procedure time in minutes	1.65	6.00	3.95 ± 1.43
Valid N (listwise)

Table 3 Mean and standard deviation of procedure time and stain size (%)

Categorized stain (%)	Procedure time mean (min)	Procedure time (min, s)	n	Std. deviation
Small	3.66’	3’40”	24	1.64
Medium-Sized	4.08’	4’05”	42	1.36
Large	4.03’	4’02”	18	1.31
Total	3.95’	3’57”	84	1.43

Table 4 Mean and standard deviation of enamel loss and stain size

Stain size in mm2	Mean enamel loss in microns (µm)	n	Std. deviation
Small	234	24	110.5
Medium-sized	232	42	105.2
Large	239	18	106.5
Total	234	84	105.8

Table 5 Kruskal-Wallis statistical test grouping variable: categorized stain percentage and effectiveness percentage

	Mean effectiveness percentage
χ2	4.3
Df	2
Asymp. Sig.	0.117

Table 6 Descriptive statistics by groups of stain size and effectiveness

Categorized Stain percentage	Mean	n	Std. deviation	Minimum	Maximum	Median
Small	93.3	24	14.14	52.18	100.00	100.00
Medium	89.2	42	14.54	54.30	100.00	98.90
Large	90.5	18	10.40	69.40	100.00	91.74
Total	90.6	84	13.61	52.18	100.00	100.00

Table 7 Nonparametric Kolmogorov-Smirnov test

		Enamel loss in μm
n		84
Normal Parameters1,2	Mean	234.05
	Std. Deviation	105.75
Most Extreme Differences	Absolute	0.20
	Positive	0.17
	Negative	-0.20
Kolmogorov-Smirnov Z		1.81
Asymp. Sig. (2-tailed)		0.003

¹Test distribution is normal.

²Calculated from data.

Table 8 Mann-Whitney U statistical test for the variable categorized procedure time

	Enamel loss in μm
Mann-Whitney U	440.50
Wilcoxon W	1665.50
Z	-3.88
Asymp. Sig. (2-tailed)	0.000

Grouping variable: categorized procedure time.

Table 9 Mean, minimum, maximum, median, and standard deviation of enamel loss and procedure time

Enamel loss in μm
Categorized procedure time	Mean	n	Std. deviation	Minimum	Maximum	Median
1 - 4.00 min	196.12	49	100.76	100	450	200
4.01 – 6 min	287.14	35	89.4	100	450	300
Total	234.05	84	105.75	100	450	225